Wednesday, October 16, 2013

Beauty Myths: Should You Be Worried About Mineral Oil?

Unknown asks, "Can you do a post on your thoughts on Mineral Oil in skincare? There's lots of debate on if its good or bad for your skin, I'd like to see you science it up."

This seems like a great topic for some beauty myth-busting!

First of all, what the hell is mineral oil?

Mineral oil is any alkane between 15 and 40 carbons that didn't come from a plant or animal-based source. That means it's just some nice, simple carbons, with hydrogen atoms attached by single bonds. Typically, mineral oils are produced from a petroleum distillate. The term was originally coined in the 18th century to refer to crude oil byproducts. (By the way: add some fragarance and BAM, you get baby oil.)

There are three big reasons that people cite for their opposition to mineral oil:
1. It comes from petroleum! Petroleum is scary!
2. YOU'RE GOING TO GET CANCER.
3. It will clog your pores and you will be a pizza face forever.

I am going to address these arguments separately.

The "petroleum is scary" argument: Puh-leeze. This is prima facie anti-science. If you don't understand chemistry, you can make lots of things sound frightening based on their component parts. But those of us who took high school science classes know that sodium may explode and chlorine may poison us, but sodium chloride just gives us delicious french fries. Both petroleum and mineral oil may contain hydrocarbons, but you need to address the actual product in question.

The "you're going to die a long and terrible death of cancer" argument: The problem here comes from a lack of distinction between unrefined and refined mineral oil. The World Health Organization classifies untreated mineral oils as Group 1 carcinogens, meaning that they are definitely carcinogenic to humans. The thing is, no one is trying to get you to put unrefined mineral oil on your face. Refined mineral oil, meaning that clear mineral oil you might buy at the drugstore, is classified as Group 3, meaning that there is no reason to suspect that it is carcinogenic.

The "look at your ugly acne" argument: This argument stems from the 1970s when dermatologists were, as a profession, concerned with a condition they termed "acne cosmetica", or acne that is aggravated by cosmetic use. (Now, with modern cosmetic chemists on the job, this diagnosis is all-but-nonexistent!) However, when the American Academy of Dermatology (AAD) convened to look at the evidence against mineral oil... it turned out there wasn't any. As of now, there is no evidence that mineral oil is prone to skin-ruining. As Joseph DiNardo notes, "Based on the animal and human data reported, along with the AAD recommendation, it would appear reasonable to conclude
that mineral oil is noncomedogenic in humans."

I have enough zits already, thanks.

(It is worth noting that this doesn't mean that you personally as an individual human being won't find that you are sensitive to mineral oil. If you have a reaction to it, don't use it.)

We've established that mineral oil wasn't sent from the devil himself to ruin your good looks and health. Why might mineral oil be a good thing in makeup or skincare?

Since mineral oils are big, long chains of carbon, they are way too large to penetrate your face. Instead, they sit on top and block water loss, making them an effective occlusive moisturizer. It is also effective at staying on the skin, even if you exercise or dump your head in barrels of water or whatever it is that the kids are doing these days. Rawlings and Lombard add, "Mineral oil is an efficacious skin moisturizer providing occlusivity
and emolliency. Its occlusive effects lead to increases in stratum
corneum water content by reducing transepidermal water loss. Through
this mechanism, mineral oil is used to treat dry skin conditions in both
leave-on and wash-off applications. It has been shown to improve skin
softness better than wax esters, triglycerides and fatty acids. Its
effect is largely confined to the epidermal layers, and as a result of
its limited penetration, it is considered to be a very safe ingredient
for cosmetic use."

The scientific literature is very clear clear: if you want to try mineral oil, go for it! Slather that shit on!

19 comments:

I don't have a dog in this fight (whatevs) but I did read a counter-argument / less scientific internetspasm that suggested that sure, use mineral oil, but don't use it under anything with active ingredients you expect to actually work (since the mineral oil would be a barrier cos of that whole occlusivity thing). Agree or disagree?

Also, what the hell do you actually use this stuff FOR? Is it good for something? Does this work on chapped dry winter horribleness, and is it time I got on the bandwagon? (I had a young child's unreasonable/psychotic phobia of Vaseline so I feel like I may be avoiding this out of association.)

One comment I see a lot against mineral oil and petroleum jelly use on the face is that it doesn't let the skin "breathe." I think there's another point you could elaborate on: the science of skin. Or maybe that's another post altogether.

I just did a post about mineral oil (baby oil) on my blog the other day. It was of course far less scientific. Would you mind if I put an update in it with a link to this post, since mine was advocating the use of it? I think this is some great info, but science just isn't my wheelhouse (still, I love reading your blog regardless).

Thanks! I kind of like the stuff for using after a shower and sometimes, just occasionally, when my skin on my face is flaking off - I will rub it on my face out of desperation. It really does work and it is cheap cheap cheap. :)

Hi! I've been a quiet reader of your blog and I must say that yours is the smartest blog I have ever come across! And the biting humor! I wish there were more blogs like yours. I have a question for you (just in case there's a scientific basis for it)...is skin purging real? I sometimes like to try new skincare products because my skin isn't really the best (argh why is it so hard to have a pimple-free face!?!), and I usually hear dermatologists say that with new skincare, the skin problems would turn worse before they get better. How long do I have to stick with a product if I seem to be badly reacting to it? Help please!

Oh gosh. I can probably write about this later. In the meantime: there are certain ingredients that may give a "purge" effect, although it's a bit of a misnomer since nothing is being purged! I'd talk to your derm, though, not me, if you have a concern about a product.

Sorry I'm late to the party having just discovered your blog, but I had to comment on #3. I accept that mineral oil is too large to penetrate the pores, yes. I don't know if you have much of a background in microbiology, but in some tests we use mineral oil specifically to create anaerobic conditions for certain tests. The anaerobic condition helps non-aerotolerant (facultative/obligate anaerobes) get happy, grow, and produce whatever compounds we need for biochemical reactions. I wonder if mineral oil on the skin also causes the same types of bacteria to grow happily in the pores and cause acne. What are your thoughts?

Your view is only looking at the cosmetic point of view without looking at skin as a biomass of human cells working together with millions of microbes. The mineral oil does affect them and inturn affect skin and waste management (sweat glands) system of the body ending in various diseases. Modern scientific studies are often short sighted and when they discover the broader picture have to re-correct the old flaws. The common ignorant public is the scape goat!